I have both Top853 and Willem brand new I am trying to prgram 2732 and 2764 I have Erase them for 2 hours and I set the Vpp at 21v for the 2732 I get a message saying Device is not Empty $000000 from Willem and I get A Error address from Top853 I do not get any Error from 27C256 and 27C512 only from 2732 and 2764 I setup every thing by the book for the Eprom Programmer.